A six-year hospital-based surveillance study on burden of esophageal candidiasis in Gangtok, Sikkim

Abstract

Background and objectives: Esophageal candidiasis once thought to be restricted amongst immunocompromised patients is being increasingly reported among non-immunocompromised individuals. It is debilitating and if not treated well may cause chronic long-lasting infections. The objective of this study was to identify the various species of Candida causing esophageal candidiasis and analyse their antifungal susceptibility pattern.

Materials and methods: This was an observational, prospective study. Total of 108 patients who attended the Gastroenterology Department of Sir Thutob Namgyal Memorial Hospital, Govt of Sikkim, Gangtok, India between July 2012 - May 2018 were included in the study. They had complaints of upper gastrointestinal disturbances and chronic dyspeptic symptoms that required an endoscopy. Esophageal biopsy and brushings were taken and were transported to Microbiology Department. They were subjected to microscopic observation, fungal culture on Sabourauds dextrose agar. Preliminary species identification was done by chlamydospore formation and growth characteristics on CHROMagar Candida. Species confirmation and antifungal susceptibility testing was done on VITEK 2 system at Microbiology Department, Kasturba Medical College and Hospital, MAHE, Manipal, Karnataka, India.

Results: A total of 108 patients were screened among which 73 samples were positive for Candida species and species identification and antifungal susceptibility was performed. Forty fiveisolates were found to be C. albicans, 8 were C. glabrata, 4 were C. tropicalis, 3 were C. lusitaniae 2 were C. krusei, 2 were C. lipolyticaand 1 was C. parapsilosis. Eight isolates could not be identified and were recorded as Candida spp. C. albicans isolates were predominantly sensitive strain with susceptibility of 95% for both amphotericin B and fluconazole and 100% for caspofungin. C. glabrata showed high resistance to fluconazole with one isolate showing intermediate resistance to caspofungin.

Conclusion: Upper gastrointestinal symptoms even in non-immunocompromised patients need to be screened by endoscopy to rule out esophageal candidiasis. With the emergence of drug resistant non albicans Candida species diagnostic testing laboratories should include Candida species identification and antifungal susceptibility testing facility to provide effective patient care.

Keywords: Amphotericin B; Antifungal; Candida; Candidiasis; Caspofungin; Endoscopy; Esophagitis; Fluconazole.

Fig. 1.

CHROMagar Candida - green apple colonies of C. albicans, light pink colonies of C. glabrata and steel blue colonies of C. tropicalis

Fig. 2.

Endoscopic picture showing white plaques (arrow head) which were sent for culture

Fig. 3.

Epidemiological map showing the distribution of patients with longitude and latitude – Map created with open source software called Quantum GIS.

Fig. 4.

Total Candida isolates. The numbers over the graph depict numbers isolated.